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The current study examines the antimicrobial and antioxidant properties of different extracts of the microalga Dunaliella salina Teodoresco (Dunaliellaceae), their fatty acid composition and the antimicrobial activity of the oil. Antimicrobial and antioxidant activities were evaluated by obtaining extracts of D. salina in n-hexane, dichloromethane, ethanol, and methanol. To evaluate the antimicrobial activity, the extracts, and fatty acids from D. salina were assessed by the disc diffusion and microdilution techniques against pathogenic microorganisms including fish and clinical/food-borne. The MBC or MFC values of the extracts and fatty acids ranged from 0.63 to 10.00 mg/ml. The antioxidant activity was studied by phosphomolybdenum and DPPH assays and ß-carotene/linoleic acid tests. In addition, the total phenolic and flavonoid contents were evaluated and the fatty acid composition was determined using gas chromatography. Palmitic, alpha-linolenic, and oleic acids were discovered to be the major components of the fatty acids. These findings have demonstrated that the extracts and oil from D. salina could be used as natural antimicrobials and antioxidants in the food/feed and pharmaceutical industry and as a biodiesel because of its high unsaturated fatty acid content.

The methanol and aqueous extracts of three endemic Centaurea species (C. polypodiifolia var. pseudobehen, C. pyrrhoblephara and C. antalyense) were investigated for their antioxidant and cholinesterase inhibitory activities. The antioxidant activities of these extracts were evaluated by in vitro models including, phosphomolybdenum assay, free radical scavenging assays (DPPH and ABTS), β-carotene/linoleic acid test system, metal chelating assay, FRAP assay, ferric and cupric reducing power. Cholinesterase inhibitory activities were examined using Ellman's colorimetric method. Total phenol, flavonoid, and saponin contents were also measured. Among the six Centaurea extracts evaluated, the highest antioxidant abilities were obtained from C. polypodiifolia var. pseudobehen. Methanolic extracts from C. polypodiifolia var. pseudobehen and C. antalyense had a noticeable inhibition towards AChE and BChE. These findings suggest that Centaurea species could be an anticholinesterase agent and antioxidant resource in some industries, such as food, pharmacology, and cosmetics., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The Isatis species has antibacterial, anticancer and antiviral properties and these important endemic plants grow widely in various parts of Anatolian-Turkey. In the present study, the antioxidant activities of Isatis floribunda Boiss. ex Bornm. flower and root extracts were determined with total antioxidant activity, free radical scavenging activity, ferric ion reducing power, and cupric ion reducing antioxidant capacity assay. The total phenolic compounds and flavonoids were also examined for the extracts. The antimicrobial activities of the extracts were investigated by using the disc diffusion and microdilution-broth methods against human and fish pathogen microorganisms. The phenolic composition of I. floribunda root methanolic extract was analyzed by high performance liquid chromatography (HPLC). The major component in the extract was cholorogenic acid (1980.20 µg/g). The cytotoxic effect of the methanolic root extract was also tested on human breast cell (MCF12A). The results showed that I. floribunda could be used as a natural source in the food and feed industry and clinical and food chemistry, and that the antimicrobial agents could be used against human and fish pathogens.

Centaurea species are used for the treatment of various ailments in the popular medicine in some countries. This study was designed to examine antioxidant potentials and fatty acid profiles of five Centaurea species from Turkey flora. Antioxidant properties of methanolic extracts from these species were evaluated by six different methods: phosphomolybdenum assay, free radical scavenging assay, β-carotene/linoleic acid test system, metal chelating activity, ferric and cupric reducing power. Total phenolic and flavonoid concentrations of each extract were also determined using the Folin-Ciocalteu reagent and aluminum chloride. The results of these assay showed a significant antioxidant capacity in all researched extracts. Centaurea cheirolopha extract, with the highest amount of total phenolic and flavonoids, showed the highest antioxidant activities in all assay, except for metal chelating. Fatty acid profiles of these species were examined by GC-FID and 30 fatty acids were identified. Palmitic, linoleic, oleic, and linolenic acid were detected as the main components. The results of the study indicated that the Centaurea species can be considered as a source of new natural antioxidants and unsaturated fatty acids for food, cosmetic and pharmaceutical industries., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Antioxidant capacities of methanolic extract and fatty acid composition of three Centaurea species were investigated. The antioxidant capacity of the extracts was evaluated by different assays, including total phenolic content, phosphomolybdenum assay, free radical scavenging activity (DPPH assay), beta-carotene/linoleic acid bleaching assay, iron (III) and cupric reduction assay. The findings showed that the methanolic extract of Centaurea pulchella has the strongest antioxidant capacity compared to other two Centaurea species. The order of the antioxidant properties of Centaurea species were C. pulchella>C. patula>C. tchihatcheffii. Thirty fatty acids were identified in the oils of three Centaurea species. The major fatty acids of these species were found to be linoleic acid from C. pulchella and C. tchihatcheffii, and alpha-linolenic acid from C. patula. The study concluded that the Centaurea species can be used as a source of natural antioxidants and essential fatty acids., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

In this study, 24 organochlorine pesticide residues in 109 different honey samples collected from stores and open markets in Konya, Turkey were analyzed by gas chromatography-electron capture detection. Aldrin, cis-chlordane, trans-chlordane, oxy-chlordane, 2,4(')-DDE, and 4,4(')-DDE were found in all honey samples. The mean value was 0.0540 microg g(-1) for oxy-chlordane. In the 55 samples of 109, levels of organochlorine pesticide residues of oxy-chlordane were determined as higher than those of Turkish Alimentarius Codex maximum residual limits (MRLs). Other organochlorine pesticide residues also exceeded MRLs except for cis-heptachlor epoxide and alpha-hexachlorocyclohexane. Since all of the honey samples are found contaminated and most of these samples exceeded MRLs, a control of organochlorine pesticide residues in honey is necessary for consumer health.

The present study has been carried out to evaluate the organochlorine pesticide contamination in wheat from Konya region. This region is the largest area of cereal production in Turkey. The contamination level has been determined according to the European Community Directives. Different wheat samples (36) were obtained from local farmers and wheat factories in this region. All the wheat samples examined were found to be contaminated by organochlorine pesticide residues of cis-Chlordane and methoxychlor. Chlordane isomers, methoxychlor, DDT and its metabolites, aldrin, beta HCH, heptachlor and lindane have been found to be the highest organochlorine pesticide residues. In some of these samples, various organochlorine pesticide residues have been determined to be higher than European Community maximum residual limits. The residues of aldrin in one sample, trans-Chlordane in one sample, oxy-chlordane in eight samples and methoxychlor in one sample were found to be in excess of EC MRLs. Since most of the samples have been found to be contaminated with residues and some residues exceed EC MRLs, a control of organochlorine pesticide residues in wheat is necessary., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)